在ActionPerformed上更改JButton颜色

Question

Despite my efforts of changing the color of my buttons, and reading everywhere on how to do it, my code still does not produce the desired effect. How can I change the color of a JButton when clicked?

public void generateButtons
{
  //Global field
  firstBoard = new JButton[9][9];

        for(int x = 0; x < firstBoard.length; x++)
        {
            for(int y = 0; y < firstBoard[0].length; y++)
            {
                firstBoard[x][y] = new JButton();
                firstBoard[x][y].setActionCommand("0|" + (x + (firstBoard.length * y)));
                firstBoard[x][y].addActionListener(this);
                //firstBoardPanel.add(firstBoard[x][y]);
            }
        }
}

@Override
    public void actionPerformed(ActionEvent e)
    {
        if(e.getSource() instanceof JButton )
        {
            System.out.println(parseActionCommand(((JButton)e.getSource()).getActionCommand()));
            ((JButton)e.getSource()).setBackground(Color.BLUE); 
            ((JButton)e.getSource()).setContentAreaFilled(false);
            ((JButton)e.getSource()).setOpaque(true); 
        }
    }

Answer 1

Try repainting the container which contains that button.

button.getParent().validate();
button.getParent().repaint();

Answer 2

This is not an answer, but an extended test case to test the difference between Mac OS Look and Feel and Nimbus, which when run on Windows OS, works

It appears, this became an answer...

Try this to start with...

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UIManager.LookAndFeelInfo;
import javax.swing.UnsupportedLookAndFeelException;

public class ChangeButton {

    public static void main(String[] args) {
        new ChangeButton();
    }

    public ChangeButton() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TestPane extends JPanel implements ActionListener {

        private final JButton[][] firstBoard;

        public TestPane() {
            setLayout(new GridLayout(9, 9));
            firstBoard = new JButton[9][9];

            for (int x = 0; x < firstBoard.length; x++) {
                for (int y = 0; y < firstBoard[0].length; y++) {
                    firstBoard[x][y] = new JButton();
                    firstBoard[x][y].setActionCommand("0|" + (x + (firstBoard.length * y)));
                    firstBoard[x][y].addActionListener(this);
                    add(firstBoard[x][y]);
                }
            }
        }

        public void actionPerformed(ActionEvent e) {
            if (e.getSource() instanceof JButton) {
                System.out.println((((JButton) e.getSource()).getActionCommand()));
                ((JButton) e.getSource()).setBackground(Color.BLUE);
                ((JButton) e.getSource()).setContentAreaFilled(false);
                ((JButton) e.getSource()).setOpaque(true);
            }
        }
    }

}

Then replace UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); with this...

for (LookAndFeelInfo info : UIManager.getInstalledLookAndFeels()) {
    if ("Nimbus".equals(info.getName())) {
        UIManager.setLookAndFeel(info.getClassName());
        break;
    }
}

And try again

Answer 3

Dont directly use the e.getSource() you need to reference it to an Object first and this use it:

example:

ublic void actionPerformed(ActionEvent e)
{
    Object ob = e.getSource();
    if(ob instanceof JButton )
    {
        System.out.println(parseActionCommand(((JButton)e.getSource()).getActionCommand()));
        JButton button = ((JButton)ob);
        button.setBackground(Color.BLUE); 
        button.setContentAreaFilled(false);
        button.setOpaque(true); 
    }